Paper machine suction box cover



July 6, 1954 G. J. SCOFIELD PAPER MACHINE SUCTION BOX COVER Filed July 27, 1950 o G EQQIW INVENTOR.

Patented July 6, 1954 PAPER MACHIN E SUCTION BOXCO'VER '-;Gilbert'-J.';Scofield, Loudonville, N. Y.

I Applicationiuly 27, 1950,;SerialNo;I76',208

(Cl.: :92.i51)

4.C laims.

1 This. inventionrelates to-improvements in-suction devices and is directed more particularly to improvements in *suction'apparatus adapted for .use withpaper'making apparatus but it-is=not necessarily limitedthereto.

The' principal objectsof theinvention are the provision of a. suction'device'having a plurality of openings therethrough which are-so formed and arranged as toprovide a maximum suction area and a'minimum'i'friction' areawhile-at the same time the device is durable and strong.

The novel features of the' invention for' purposes of disclosurewill -be"described in-connection "with a"'coveror suctionplateof a suction-box such as is employedton a-Fourdrinier paper mak ing machine.

These suction plates *hereinaf-tercalled plates have beenformed'fromwood, metal-and the like and have been provided witha multiplicityof "openings. The openings have been holes or-slots of all forms and arrangements.

' The Fourdrinier wire-orfelttra'vels acrossthe upper "side of "the plate so that there is friction between the wire or feltand the platebetween theiopem'ngs. "This, to a considerable-degree, in-

*fluences the speed of operation of the paper ma- 'chine'an'd iszobj actionable.

"recent -years the width of paper machines "has increased. This'has called'forsuction boxes and suction plates of longer lengths. supporting inthese-longer lengths; regard I must "be *had' for strength so 7 that the spacing of the openings "has been infiuencedby the necessity for strength and "rigidity.

"The result has been that the=-plates and suction boxes have a considerable transverse width in. order to -obtain the required suction area. and at the same time the friction areahas increased.

According to this invention, a plate is provided with =openings of novel form which are so arxrangedithat a maximumvofsuction area and a eminimu m'of friction area. -.is -providedwithout the sacrifice of strength and ruggedness thereby makingit possible to providea-plate for-machines of extreme width without increasing the :transverse width of the plate. It ispossible to' obtain :'the increased suction area and decreased'ifricztionzarea with a plate ofwless transverse width than normal.

Withthe .foregoing. -and .various other novel "features and advantages andaiother objects of; my invention as-' will- -become'-more=:apparent as the description proceeds, the invention consists in certain novel features .of i construction .and' in the combination and arrangement or partsaswill be To be self- A -'-herein'after more particularly pointed outin the claims hereunto annexed and more fully described and'referred to in connection With""the accompanying drawings wherein:

Fig. 1 is a plan view of asuction box' embod-ying the novel features of the invention;

'Fig. 2 is'an--end-elevational view of theplate shown iIrFig. l;

- Fig; '3 is an enlarged plan viewof a portion of-the -plate of Fig. 1; "Figs; 4, 5 and Gare-sectional elevational views on the lines 4-4, 55 and 6-4? of-Fig. 1;- and Figs. '7, 8, 9 and-lO-are sectional elevational "viewssimilar td-Figs. 4, Sand firespectively'and showing modifications of the invention.

Referring now to the drawings more in'detail,

the invention'will befully described.

-A- suction plate is shown in Figs. 1 and 2 which 'will beof greater longitudinal length than transverse widthfi The plate is secured to a suction are spaced transversely of the plate.

-The openings- 6extend through the plate and in general will have downwardly and upwardly extending diverging sides to provide restricted throats 8;

The form of openings results in an-increased velocity of water and air as the suction boxcar- =rying the'plate isconnectedto a source of suction--and with the'wire'or felt'passing across carrying a wet' web.

Adjacent-openingsfi of the longitudinal rows thereof are relativelyspaced along said rows so "that upper portions "of said openings intersect as at ID (-see Figs. '3' to 6 inc).

By this intersection, portions of the plate between adjacent openings are disposed below the sides or faces-of the plate so that the openings of a row thereof are in communicationand form longitudinal channels along the rows of holes.

By "providing the openings through the plate having downwardly and upwardly diverging sides,

"the'uppersides of the holes are larger than would be the case and therefore of greater area than if the holes were straight. Since the holes at "upper'and'lower sides intersect at Hl-as stated iabove'an'dshown in Fig. 4;there are no portions of 'thesurfacepftheplate between theholesbf the rows. That is, the portions of the plate between the holes of the rows are disposed below the surface of the plate and therefore provide the longitudinal channels. In this way there are longitudinal channels spaced transversely of the plate and the channels have longitudinally spaced holes therefrom. The holes of the rows thereof being of the form described and related as they are provide a greater suction area than if straight holes were employed, If straight holes or slots of a dimension approaching that of the holes at the surface of applicants plate were used there would be no plate strength.

Thus the structure is such as to possess the functions and advantages of openings and slots of prior art suction plates.

The openings of the rows are staggered relatively to adjacent rows thereof as shown in Fig. 3 and the openings of one row are spaced somewhat from the openings of adjacent rows.

Sections I l transversely of the plate between openings of adjacent rows thereof as on the line E have a considerable width as indicated by It in Fig. 6. These sections, of which there are many, provide stiifness and strength to the plate permitting the arrangement of openings de scribed. There are elongated sections between the rows of openings which connect with the sections l4 whereby the plate is of such strength and rigidity that it may be made in any length.

The construction is such that there is maximum suction area and minimum friction area which together with the novel form of openings make it possible to operate a paper machine at increased speeds.

That is, the surface speed of a wire or felt is not as adversely affected by friction as formerly. The increased suction area and form of openings which bring about increased velocity cooperate with the reduced friction area for increased speed and production.

By comparison of a plate of this invention with prior art plates, the increased suction area and decreased friction area are very marked.

By calculating the suction and friction areas of prior art plates with the plate of this invention, the plates being of the same size, it was found that the plate of this invention had approximately twice the suction area and approxi mately one-half the friction area of the prior art plates.

By means of the invention, it is therefore possible to greatly increase and decrease the sue-- tion and friction areas over prior art plates with a plate of the over-all dimensions of the prior art plate. Or a plate of one-half the width of a prior art plate may be employed which will have a suction area equal to or greater and a friction area no greater or less than of the prior art plate.

To contribute to the greater suction area the rows of openings may be closely spaced, as shown, and this close spacing provides continuity of suction. That is, the wire or felt passes immediately from one row of openings to the next. In prior art devices there are substantial transverse spaces between openings.

Figs. 7 to inc. show various modifications of the openings 6 which have restricted throats 8 and there may be other forms providing the increase in velocity all within the scope of the invention.

lhe invention may be embodied in other specific forms without departing from the essential characteristics thereof. Hence, the present embodiments are therefore to be considered in all respects merely as being illustrative and not as being restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all modifications and variations as fall within the meaning and purview and range of equivalency of the appended claims are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the United States is:

l. A cover for the suction box of a paper making machine adapted to support a traveling ifiourdrinier wire comprising, an elongated platelike member having flat parallel upper and lower said member being provided with transversely spaced rows of longitudinally spaced round suction holes extending therethrough from face to face thereof, said holes having sides converging downwardly from the upper face of the member and said holes being relatively spaced so that adjacent converging side portions of adjacent holes of the rows thereof intersect below the plane of the upper face of the member thereby connecting upper portions of said adjacent holes and providing transversely spaced longitudinally extending channels open at the upper face of the member having suction holes spaced longitudinally thereof and extending downwardly from said channels through said member.

2. A cover for the suction box of a paper making machine adapted to support a traveling Fourdrinier wire comprising, an elongated plate like member having flat parallel upper and lower faces, said member provided with transversely spaced rows of longitudinally spaced round suction holes extending therethrough from face to face thereof, said holes having sides converging downwardly and upwardly from upper and lower faces of the member and said holes being relatively spaced so that adjacent converging side portions of adjacent holes of the rows thereof intersect below the planes of the upper and lower planes of the upper and lower faces of the member thereby connecting said adjacent holes at their upper and lower ends and providing transversely spaced upper and lower longitudinally extending channels open at upper and lower faces of the member having longitudinally spaced suction holes connecting said upper and lower channels.

3. A cover for the suction box of a paper making machine as set forth in claim 1 wherein the holes of adjacent channels are staggered.

A cover of a suction box of a paper making machine set forth in claim 2 wherein the holes of adjacent channels are staggered.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain A. D. 1880 

